ABSTRACT
Hydatid cyst is one of the parasitic zoonoses caused by infection with the larval stage of Echinococcus granulosus tapeworm. The spread of this parasite is global and is of great importance in terms of public health. To date, ten different species of this parasite have been identified that differ in characteristics such as life cycle, epidemiology and pathogenesis. The purpose of this study was to determine the genotype and phylogenetic relationship of hydatid cysts isolated from livestock of Bushehr province, Iran. About 62 samples of hepatic and pulmonary hydatid cysts were collected from slaughtered animals. DNA extracted by phenol-chloroform method was amplified by PCR using primers specific for the cox1 gene. The PCR products of 50 samples were sequenced and analyzed using BioEdit software and compared with sequences in the GenBank. The phylogenetic tree was drawn using Neighbor Joining tree-NJ method, and its reliability was evaluated. Sequencing results showed that out of 50 sequenced samples, 43 samples had the genotype of Echinococcus granulosus and 7 samples had the genotype of Taenia hydatigena. By drawing a phylogenetic tree, all 43 hydatid cyst samples belonged to G1 strain. The predominance of G1 strain of hydatid cyst in livestock of Bushehr province shows the main role of this genotype in establishing the life cycle of parasite in this region and if the genotype of the parasite in dogs and humans is determined, then these findings can be used to disrupt the life cycle of the parasite and reduce the human infections.
ABSTRACT
BACKGROUND & OBJECTIVES: Leishmaniasis, known as a disease with high prevalence proportion throughout the world, is caused by protozoan parasites. Visceral leishmaniasis is the most severe form of this condition reported sporadically from all regions in Iran. Between different diagnostic tests, serodiagnosis of this infection is of utmost importance in both humans and dogs. Although rK39 ELISA test has been extensively validated in endemic areas, there are currently challenges regarding a more appropriate serodiagnostic test. METHODS: A novel multi-epitope construct was designed consisting of highexposedB cell epitopes using eight important antigens of Leishmania infantum (Gp63, KMP-11, HSP70, CPA, H2A, H3, LACK and TRYP). Our artificial sequence, a Multi-epitope Recombinant Protein (MRP), was consequently produced and purified. Then, immunoreactivity was investigated by ELISA test and western blotting as well. RESULTS: In the present study, the cutoff value (1.052) for the new MRP-ELISA was determined by receiver operator characteristic (ROC) curve analysis using 35 known positive and 20 known negative HVL sera previously tested for antibodies to L. infantum by DAT, showing a sensitivity of 93.1% and a specificity of 77.4%. The blotting test also showed a favorable band to detect visceral leishmaniasis. INTERPRETATION & CONCLUSION: According to the results, this new antigen had acceptable potential in detecting VL positive cases once western blotting was utilized, but the ELISA test did not proceed as expected for detecting true negative cases, probably due to some optimization issues.The present study is a promising start.
